body, html {
    font: 14px/1.5 "PingFang SC", "微软雅黑", "Microsoft YaHei", Helvetica, "Helvetica Neue", Tahoma, Arial, sans-serif;
    color: #1c1f21;
    background-color: rgb(238, 238, 238);
}

.chapter a{
    text-decoration: none;
    display: block;
    outline: 0;
    color: black;
    font-size: 20px;
    font-style: italic;
    height: 40px;
}

.chapter a:hover {
    text-decoration: none;
    box-shadow: 0 4px 8px 0 rgba(28, 31, 33, .3);
    border-radius: 6px;
    background-color: rgb(226, 250, 221);
}

.nav li{
    margin-top: 0;
}

body, ul, div, li, a {
    margin: 0;
    padding: 0;
}

ul {
    list-style: none;
}

li {
    border: none;
    margin-top: 10px;

}

.course-img {
    box-shadow: 0 4px 8px;
    border-radius: 10px;
    width: 80%;
    height: 250px;
    margin-left: 10px;
}

.course-info {
    width: 100%;
    font-size: 20px;
    border-radius: 10px;
    box-shadow: 0 4px 10px 0 rgba(28, 31, 33, .1);
    background-color: white;
}

.my-container {
    width: 100%;
    border-radius: 10px;
    box-shadow: 0 4px 8px 0 rgba(28, 31, 33, .1);
    margin-bottom: 20px;
    margin-top: 20px;
    padding-top: 20px;
    padding-left: 20px;
    padding-bottom: 30px;
    border: 1px solid #a9c9e2;
    background: #e8f5fe
}

.teacher-intro {
    width: 100%;
    margin-left: 0;
    text-indent: 2em;
    font-size: 15px;
}

.my-comment {
    display: none;
    border-radius: 10px;
    box-shadow: 0 4px 8px 0 rgba(28, 31, 33, .1);
    width: 100%;
    height: 300px;
    margin-top: 0;
    padding-top: 0;
    padding-left: 0;
    border: 1px solid #9bdf70;
    background: #f0fbeb
}

textarea {
    width: 90%;
    height: 200px;
    display: block;
    resize: none;
    overflow-y: auto;
    margin-left: 20px;
    border: 1px solid #a5b6c8;
    background: #eef3f7
}

.other-comment {
    margin-top: 20px;
    margin-bottom: 20px;
    border-radius: 10px;
    box-shadow: 0 4px 8px 0 rgba(28, 31, 33, .1);
    width: 100%;
    background-color: #f0fbeb;
    padding-top: 0;
}

.auto-wrap {
    width: 100%;
    height: auto;
    word-wrap: break-word;
    word-break: break-all;
    overflow: hidden;
    margin-top: 10px;
}

.course-intro {
    font-size: 14px;
    padding-bottom: 20px;
    text-indent: 2em;
}

.course-name {
    margin-top: 10px;
    margin-bottom: 20px
}

.teacher-name {
    font-size: 20px;
    margin-right: 15px
}

.learn-total{
    margin-right: 15px;
    margin-top: 10px;
}

.course-create-date {
    margin-right: 16px;
    margin-left: 2px;
    margin-top: 10px
}

.try-button {
    margin-left: 0;
    margin-top: 40px;
    display: none;
}


.purchase-button {
    margin-top: 40px;
    margin-left: 10px;
    display: none;
}

.teacher-intro p {
    font-size: 14px;
    padding-bottom: 20px;
    text-indent: 2em;
}

.chapter {
    font-size: 20px;
    border-radius: 10px;
    box-shadow: 0 4px 8px 0 rgba(28, 31, 33, .1);
    margin-bottom: 100px;
    border: 1px solid #ffdd99;
    background: #fff9ed
}

.chapter ul {
    margin-left: 32px;
    margin-right: 32px;
}

.chapter ul i {
    float: left;
    padding-top: 10px;
    padding-left: 10px;
}

.chapter ul p {
    padding-top: 7px;
    margin-left: 100px;
    display: inline
}

.chapter ul button {
    margin: 8px 12px 0 0;
    height: 24px;
    padding: 0 12px;
    font-size: 12px;
    float: right;
    border-style: solid;
    border-width: 1px;
    cursor: pointer;
    transition: all .3s;
    color: #fff;
    background-color: #f20d0d;
    border-color: #f20d0d;
    opacity: 1;
    text-align: center;
    border-radius: 18px;
    display: none;
}

.comment {
    margin-left: 0;
    padding: 0;
}

.comment img {
    border-radius: 50%;
    display: inline-block;
    height: 50px;
    width: 50px;
}

.comment button {
    float: right;
    margin-right: 35px;
    margin-top: 10px;
}

.more-comment {
    text-align: center;
    background: #fafafa;
    border-top: 1px solid #eaeaea;
    color: #666;
    padding: 15px 0;
    cursor: pointer;
    font-size: 12px;
}